Diabetes is one of so-called “lifestyle-related diseases”, and the number of patients has been increasing these days. Diabetes is caused by deficiency in function of regulation of blood glucose level, and chronic high blood glucose level leads to neuropathy in peripheral nerves and angiopathy, and finally leads to loss of sight and necrosis.
Insulin, a hormone to lower blood glucose level, is used as an anti-diabetic drug, but insulin is administered via injection, which burdens patients. Moreover, diabetes for which insulin is not effective is also known, and definite remedy has not been developed although some drugs to improve symptoms exist. Thus, anti-diabetic drug which is more effective and can be orally administered is desired to be developed.
Recently, obesity has also been a problem as one of causes for various lifestyle-related diseases, and effective agents for improving or treating obesity is desired to be developed. It is postulated that obesity is caused by impaired glucose tolerance, a condition where blood glucose level temporary increases after food intake and decreases slowly, and that improvement of the impaired glucose tolerance is effective for preventing or treating obesity.
The compound (A) shown below is called DIF-1 and was isolated from a cellular slime mold, and is known to have anti-cancer activity (Biochem Biophys Res Commun. 1997 Jul. 18; 236(2):418-22). However, it has not been known that DIF-1 and its related compounds have an activity to promote the glucose uptake of cells and an activity to lower blood glucose.
